Improved drill for boring rocks



PATENT OFFICE.

WM. BICKEL, OF POTTSVILLE, PENNSYLVANIA.

IMPROVED DRILL FOR BORING ROCKS, 84C.

Specication forming part of Letters Patent No. 48,785, dated July 18, 1865. n

. which- Similar letters rcl'er to like parts in the dit'- ferent figures.

Figures l and 2 are perspective views.

To enable those skilled in the art to fully unstand and construct my invention, I will proceed to describe it.

B represents a bit or chisel.

A and A represent bits or picks, which are attached in Fig. 1 at right angles to and upon opposite sides of thel bit'orkchisel B, these bits or picks A and A extendingin length and projecting over the bit In Fig. 2 a pick is represented at each end of the chisel.

C represents the grooves or openings through which water and excavated material m'ay escape.

The object is to combine the action of the pick and the chisel or drill. Thesepicks may vary in number, shape, and position and be adapted to rocks` of different hardness. The points of the picks extend in length beyond the end of the bitted portion.

It will be seen that the small bits or picks A and A will cut so as to leave a core in the center of the-hole, which core will be reduced by the large bit or chisel B, thus rapidly penetrating the substance bored.

This improvement may be constructedin one solid mass or piece of iron or steel, or the several bits A A and B may be separately constructed and afterward united. The latter plan will facilitate the operation of sharpening or repairing.

The action of the `drill as a whole may be compared to that of mortisin g lumber, keeping the margin ot' the hole lowest, cutting round the outside tirstand then reducing the core left.

Having described my invention, whatIclaim therein as new, and desire to secure by Letters Patent, is-

The combi nation of' pick and chisel described, the points constituting the former extending longitudinally beyond the latter, for the purpose set forth.

WM. BIOKEL.

IVitnesses:

GrIAs. D. HIPPLE, A E. A. DoBBINs. 

